private async Task <string> TrySaveFlags(FeatureFlagsViewModel model, string contentId)
{
var flags = new FeatureFlags(
model.Features.ToDictionary(f => f.Name, f => f.Status),
model.Flights.ToDictionary(f => f.Name, f => f.AsFlight()));
var result = await _storage.TrySaveAsync(flags, contentId);
switch (result)
{
case FeatureFlagSaveResult.Ok:
// The flags have been persisted. Refresh this instance's cache immediately.
await _cache.RefreshAsync();
var refreshSeconds = _config.FeatureFlagsRefreshInterval.TotalSeconds;
TempData["Message"] = $"Your feature flags have been saved! It may take up to {refreshSeconds} seconds for this change to propagate everywhere.";
return(null);
case FeatureFlagSaveResult.Conflict:
return("Your changes were not applied as the feature flags were modified by someone else. Please reload the page and try again.");
default:
return($"Unknown save result '{result}'.");
}
}
public async Task <ActionResult> Index(FeatureFlagsViewModel model)
{
if (ModelState.IsValid)
{
var result = await _storage.TrySaveAsync(model.Flags, model.ContentId);
switch (result.Type)
{
case FeatureFlagSaveResultType.Ok:
// The flags have been persisted. Refresh this instance's cache immediately.
await _cache.RefreshAsync();
var refreshSeconds = _config.FeatureFlagsRefreshInterval.TotalSeconds;
TempData["Message"] = $"Your feature flags have been saved! It may take up to {refreshSeconds} seconds for this change to propagate everywhere.";
return(Redirect(Url.Action(actionName: "Index", controllerName: "Features")));
case FeatureFlagSaveResultType.Conflict:
TempData["ErrorMessage"] = "Your changes were not applied as the feature flags were modified by someone else. " +
"Please reload the page and try again.";
break;
case FeatureFlagSaveResultType.Invalid:
ModelState.AddModelError(nameof(model.Flags), $"Invalid flags: {result.Message}");
break;
default:
TempData["ErrorMessage"] = $"Unknown save result '{result}': {result.Message}.";
break;
}
}
return(View(model));
}
private string ApplyChange <TModify, TBase>(
FeatureFlagsViewModel model,
TModify change,
ChangeType type)
where TModify : IModifyFeatureFlagsViewModel <TBase>, TBase
where TBase : IFeatureFlagsObjectViewModel
{
var validationError = change.GetValidationError(_userService);
if (validationError != null)
{
return(validationError);
}
var existingList = change.GetExistingList(model);
var existing = existingList.SingleOrDefault(f => f.Name == change.Name);
switch (type)
{
case ChangeType.Add:
if (existing == null)
{
existingList.Add(change);
return(null);
}
else
{
return($"The {change.PrettyName} '{change.Name}' already exists. " +
$"You cannot add a {change.PrettyName} that already exists.");
}
case ChangeType.Edit:
if (existing == null)
{
return($"The {change.PrettyName} '{change.Name}' does not exist. " +
$"You cannot edit a {change.PrettyName} that does not exist.");
}
else
{
change.ApplyTo(existing);
return(null);
}
case ChangeType.Delete:
if (existing == null)
{
return($"The {change.PrettyName} '{change.Name}' does not exist. " +
$"You cannot delete a {change.PrettyName} that does not exist.");
}
else
{
existingList.Remove(existing);
return(null);
}
default:
throw new ArgumentOutOfRangeException(nameof(type));
}
}
public static void AssertFlags(FeatureFlags flags, FeatureFlagsViewModel model)
{
Assert.Equal(flags.Features.Count, model.Features.Count);
Assert.Equal(flags.Flights.Count, model.Flights.Count);
foreach (var feature in model.Features)
{
Assert.True(flags.Features.ContainsKey(feature.Name));
Assert.Equal(flags.Features[feature.Name], feature.Status);
}
foreach (var flight in model.Flights)
{
Assert.True(flags.Flights.ContainsKey(flight.Name));
AssertFlight(flags.Flights[flight.Name], flight);
}
}
public static void AssertFlags(
FeatureFlags flags,
FeatureFlagsViewModel model,
bool hasLastUpdated,
TimeSpan refreshInterval,
string contentId)
{
if (hasLastUpdated)
{
Assert.True(model.TimeSinceLastRefresh > TimeSpan.Zero);
}
else
{
Assert.Null(model.TimeSinceLastRefresh);
}
Assert.Equal(refreshInterval, model.RefreshInterval);
Assert.Equal(contentId, model.ContentId);
AssertFlags(flags, model);
}